Three-dimensional dammann array generator

Abstract

A three-dimensional dammann array generator is characterized by including a two-dimensional dammann raster, a confocal lenses group formed by a first lens and a second lens, an entrance pupil, a dammann zone plate and an aberration-free focusing objective lens, which are sequentially arranged in the advancing direction of the incident uniform intensity laser plane wave, wherein the two-dimensional dammann raster is an M*N dammann raster; the dammann zone plate is a 1*Q dammann zone plate; and a focal spot of the focusing objective lens generates an M*N*Q three-dimensional laser focusing focal spot array expanding in the axial and the horizontal directions within a certain range. The three-dimensional laser focusing spots are uniformly spaced in the axial and the horizontal directions, and are regular arranged in a 'crystal grating' in space, and have equal intensity; and the laser focusing focal spot three-dimensional dammann array generated by the invention can be extensively applied to the three-dimensional laser micro nano machining including such fields as three-dimensional photonic crystal manufacture, laser paralleling particle and cell capture and three-dimensional detection.

Description

technical field [0001] The invention relates to a technology for generating a three-dimensional Damman array of a laser focused light field based on a binary optical element, in particular to a three-dimensional Damman array generator capable of realizing focused light spots of equal intensity extending along the axial and lateral directions. Background technique [0002] Since the 1960s, the invention of lasers has brought revolutionary changes to human production and life. It is precisely because of the monochromaticity, coherence and high brightness of the laser that the focusing field of the laser shows incomparable superiority in laser processing, laser surgery, optical tweezers and other occasions, and plays an irreplaceable role. However, for the traditional single-channel laser focusing, there is only one focused spot in the field after focusing, and the efficiency of laser processing and laser capture is low. Microlens array is a technology that can obtain multiple...

AI Technical Summary

Problems solved by technology

The clear aperture of the high numerical aperture objective lens is generally several millimeters, which makes the number of periods and the total number of pixels in the aperture of the three-dimensional grating based on the spatial light modulator not enough

This will greatly reduce the uniformity and efficiency of the generated three-dimensional focusing spot, and even completely destroy the three-dimensional spot effect

Therefore, this three-dimensional grating technology solution based on spatial light modulator can only be a proof of principle, and cannot be used in most practical applications.

In addition, even if the spatial light modulator can provide a sufficiently high spatial resolution, the three-dimensional grating used in this technical solution is designed within the theoretical range of scalar focusing, and cannot be used for high numerical aperture focusing

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